1. Field of the Invention
The invention relates to electrical connectors, and particularly to a card edge connector with latching arms thereof for retaining a card module therein.
2. Description of Related Art
Primarily as a result of the expansion of memory in the computer field, techniques have become known is which semiconductor devices containing memories are mounted on card modules. In most cases, card edge connectors are used for the connection of such card modules to circuit boards. Card edge connectors have a substantially C-shaped configuration in which a pair of arms are formed in positions on both end portions of an insulating housing main body which carries numerous contacts.
One example of a latch-equipped electrical connector is disclosed in U.S. Pat. No. 5,779,494. The connector accommodates memory circuit card which has recesses located in the side edges. Two latching arms are integrally formed with a housing along side edges of the housing. Each of the latching arms carries a projection portion that is engageable with the recess of the circuit card, the projecting portion has a lower portion, an upper overhanging portion that overlies the lower portion and a tapered cam surface having a descending gradient. When the circuit card is inserted into a card slot of the housing and rotated into engagement, the interior edge of the recess of the circuit card contacts the tapered cam surface of the projecting portion to exert a force on the latching arm that causes the latching arm to deflect or move outwards and back toward the circuit card. Finally, the overhanging portions overlie a portion of the circuit card around the recesses, and the lower portions fits within and engaged the interior edges of the circuit card recesses. This connector suffers from a problem that concerns the reliability of the accommodation and holding of the circuit board in a correct place. Specifically, in the connector disclosed in the abovementioned patent, the tapered cam, the upper overhanging portion and the lower portion are at the same location, the connector allows flexing of the latching arms even in cases where the recesses of the circuit card are not accurately aligned with the tapered cam of the latching arms at the time of accommodation within the connector. Accordingly, the connector is held with in the connector by the projection portions of the latching arms, awful electrical connection between the circuit card and the connector which can not be found easily is be established, even, there is a danger that the latching arms will be deformed.
Hence, an improved card edge connector is required to overcome the disadvantages of the related art.